The present invention relates to a thin film magnetic head which may be used in a magnetic reading and recording apparatus such as a magnetic disk drive, a magnetic tape drive, and so on. More particularly, it relates to a thin film magnetic head employing a magneto-resistive (MR) element which is manufactured by a use of the thin film forming technology.
The thin film magnetic head employing the magneto-resistive (MR) element is disclosed in Japanese Patent Disclosure No. 150315/1976. As shown in FIG. 7, the convention thin film magnetic head includes a substrate 301 on which a pair of yokes 302 and 303 of a high permeability soft magnetic material are formed via a insulative layer 341, the formation being by the thin film forming technology. One ends of the pair of yokes 302 and 303 form a gap 308 which generates a magnetic flux to be applied to a magnetic medium 309. The other ends of the yokes are magnetically connected by a high permeability, soft magnetic material (return path) 306 and the MR element 305. The MR element 305 has contacts 323 and 324 to supply a drive current thereto during a reading operation. The yokes 302 and 303 are provided with coils 311 and 312 to which a recording current is applied through contacts 321 and 322.
In the conventional thin film magnetic head, the track width W is determined by the thickness of the yoke. Accordingly, the track width can easily be reduced by decreasing the thickness of the yoke in order to obtain high recording density. However, the direction of the easy axis of magnetization of the MR element 305 is the same as the longitudinal direction of the MR element 305. Since the magnetic flux flows along the longitudinal direction of the MR element 305, the domain walls are generated in the MR element so that Barkhausen noise is produced in the output signal of the MR element 305 to degrade the signal/noise ratio of the output signal. Further, since the direction of the easy axis of magnetization of the yokes 302 and 303 and the return path is arbitrary, the magnetic flux does not efficiently flow through the yokes 302 and 303 and the return path. As a result, the output signal of the MR element 305 is not sufficiently strong.